Summary Imaging techniques constitute critical tools that are brought to bear with creativity and power in many aspects of modern renal research. The renal researchers who participate in this Program Project Grant require ready access to high quality imaging equipment and services. The existing Microscopy and Imaging Center core facility has been designed to meet this need. The core has been structured in a manner that unites resources and expertise from several different locations within the University into a single unified entity that can serve as an integral partner in the design and execution of imaging studies. The facility includes a full range of high quality imaging equipment, including: fluorescence photomicroscopes, fluorescence imaging systems, a new laser scanning confocal microscope, a spinning disk confocal microscope, an electron microscope and numerous devices for tissue sectioning and sample preparation. The technical staff of the core manifests decades of combined experience in imaging methodologies and technique development. The supervisory staff includes two senior scientists, both of whom have extensive expertise in the application of the various modalities of imaging to renal and physiological research. This team will work together to meet the following objectives: 1) to provide PPG group researchers with ready access to high quality imaging modalities, including fluorescence microscopy, laser scanning confocal microscopy, real time imagining of physiological parameters in cells and tubules and electron microscopy; 2) to provide PPG group researchers with expert sample preparation and processing for light and electron microscopy; 3) to provide PPG group researchers with expert assistance in the generation, interpretation and quantitation of static images, including those documenting organ structure, renal histology, and the subcellular localizations of renal proteins; and 4) to provide PPG group researchers with access to the equipment and expertise required to produce dynamic images of living cells and tissues, including in vivo assessment of organ structure, measurements of intracellular ion concentrations, and real time observations of protein trafficking.